Studies are proposed whose aim is the characterization at the molecular level of receptor sites in the brain which are implicated as being affected abnormally in schizophrenia, Parkinson's disease and other related conditions, and as sites of action f antipsychotic drugs. The studies involve the synthesis of rigid analogs of dopamine and various classes of neuroleptics, and determination of their affinities toward such sites, and of covalent attachment of suitably modified neurochemically active compounds to such brain sites using photochemical techniques. Specificity of binding and attachment to dopaminergic sites from different regions of mammalian brains is also to be studied.